The invention concerns a current-carrying lead, in particular connecting lead and heating tape, for a plug connector, comprising at least two litz wires that are partially surrounded by an electrical insulation. The invention concerns also a plug connector comprising such a current-carrying lead and comprising at least one sealing device provided for the lead that comprises at least one sealing member that comprises at least one elastically deformable sealing part that, by introducing a force that is acting in the longitudinal direction of the lead, is elastically deformable transversely to this longitudinal direction against the lead, wherein the sealing part is deformable elastically by at least one wedge slider that is provided with a conical surface that interacts with a conical surface of the sealing part. The invention also relates to a plug connector in which the lead is supported by a multi-point support in a strain relief device that has four pressure members which are positioned opposite each other in pairs, respectively.
Current-carrying leads in the form of connecting leads and heating tapes are known which are connected to each other by means of the plug connector. By means of the heating tapes, pipes, containers, channels and the like are maintained at defined temperatures. For example, the heating tapes are attached to conveying lines in order to keep the medium flowing within the conveying lines at a defined temperature so that it is flowable or can stream. Often, at the end of the heating tape moisture will deposit and thereby change the leakage current resistance of the heating tape. In particular in moist or wet conditions of use, the moisture penetrates as a result of capillary action or moisture is generated by a pumping effect which is caused by cooling or heating. Between the litz wires of the heating tape, an initially small, over the course of time greater, moisture collection is produced on which electrical leakage currents can flow. Because of this, there is the risk that the heating tape will suffer from scorch marks between the two litz wires. Progressively, the leakage current resistance can even drop so far that short circuiting may be produced.
Moreover, the contacting action of heating tape and connecting lead must be protected from environmental effects in order to avoid short-circuiting by moisture penetration between the potentials of the litz wires.
For this purpose, glands with matched nut are known through which the electrical lead is projecting. The gland is elastically deformed in radial inward direction so that it contacts seal-tightly the heating tape. This deformation of the gland causes flexing, i.e., a deformation in circumferential direction. This has the result that the sealing effect is reduced because due to the flexing movement passageways inwardly into the plug connector are formed. Accordingly, through the gland moisture from the exterior can penetrate and can cause the afore described problems within the plug connector.
The invention has the object to configure the current-carrying lead of the aforementioned kind and the plug connector of the aforementioned kind in such a way that, while providing a simple configuration and inexpensive assembly, it is ensured that a leakage current generation due to moisture in the plug connector is avoided.